Simple Rain Detector Alarm

This rain detector alarm circuit project is an very simple circuit , that will start an audio warning , if the liquid is present on the sense pad . This rain detector alarm circuit diagram is based on two transistors BC547 and BC557 . When the sense pads conducts , Tr1 and Tr2 will generate a pitch sound .

This circuit needs a 12 volts power supply circuit and the speaker needs to have a 32 ohms . The sense pad can be constructed on a small piece of printed circuit board .

Note : Sensor automatically goes high in certain seconds in regular period for simuation purpose, In realtime sensor gives high when rain drop detected.

anonymous
said:

6 years ago

Could you please explain the working of each component in the circuit?